How to Check Your Water Meter for a Hidden Leak

Your water meter is the most useful diagnostic tool you already own. It measures every drop of water moving through your plumbing, which means it can tell you whether something is using water even when every faucet in the house is off. Here’s how to run the test properly and what the result actually means.

Step-by-Step: How to Check Your Meter

1. Turn off all water use. Faucets, showers, washing machine, dishwasher, ice maker, irrigation system — anything that draws water.
2. Find your water meter. In most West Palm Beach homes it’s in a small in-ground box near the curb or property line, usually with a lid marked “water.”
3. Record the reading. Note the exact numbers, including the small sweep or triangle dial if your meter has one — that dial moves with even a trickle of flow.
4. Wait one to two hours. Don’t use any water during this window. Longer is fine if you can manage it — two to three hours gives a clearer result for a slow leak.
5. Check the reading again. If the numbers moved, or that small leak-indicator dial is spinning, water is flowing through the system somewhere.

What the Result Can — and Can’t — Tell You

A moved reading confirms that water is being used somewhere on your property while everything should be off. What it can’t tell you is where. The meter measures total flow for the whole property, not which line or fixture it’s coming from — that’s the difference between knowing you have a leak and knowing where to find it.

Situations Where the Test Can Be Misleading

A few things can throw off your result, so rule these out before assuming a leak:

• An automatic irrigation system that kicked on during the test window
• An ice maker or water softener mid-cycle
• A running toilet that isn’t obviously audible
• A pool autofill valve topping off the pool

If none of these apply and the meter still moved, that’s a genuine sign of a leak somewhere in your system — inside the house, under the slab, or in the line running underground between the meter and the house.

What to Do If You Suspect a Leak

Start by checking the obvious spots — under sinks, around the water heater, behind the toilet — since an easy-to-see leak doesn’t need special equipment. If nothing is visible but the meter confirms flow, the leak is hidden, which is where professional water leak detection comes in. Acoustic and pressure-testing equipment can isolate which section of your plumbing is affected without opening up walls or floors on a guess.

When It’s Likely an Underground Leak

If you’ve checked every fixture and appliance inside and nothing explains the movement, the leak may be outside — in the buried line between the meter and your house, or in an irrigation line. A soggy patch of lawn, a section of grass that’s greener than the rest, or lower water pressure throughout the house are common companion signs. Our underground leak detection page walks through how that type of leak is traced and located without digging up the whole yard.

Next Step

The meter test takes under two hours and costs nothing, which makes it the right first move whenever you suspect a leak. If it confirms water is moving and you can’t find the source yourself, that’s your cue to bring in equipment built for the job rather than guessing at where to start.